Valvular mechanism.



No. 801,058. PATENTED 00T.3, 1905. H. S. AYLING. VALVULAR MECHANISM.

APPLIGATION FILED 00T. 17, 1904.

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Arron/ms PATENTED OCT. 3, 1905'.

H. S. AYLING.

VALVULAR MEGHANISM.

APPLICATION FILED 00T.1v.19o4.

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INVENTOR ffm@ .Sigg/wg ATTORNEYS WIT/VESSES:

N0. 801,050. PATENTED 00T. s, 1905.

H. s. AYLING VALVULAR MBGHANISM.

APPLICATION FILED 0OT.17,1904.

4 sHnBTs-SHET a,

PATENTED OCT. 3, 1905K.

H. S. AYLING.

VALVULAR MBCHANISM.

APPLIUATION FILED 00T.17,19o4.

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ATTORNEYS UNITED sTATEs PATENT oEEicE.

HENRY S. AYLING, OF BLOOMINGTON, ILLINOIS, ASSIGNOR OF ONE-HALF TO EDW'ARD AUTEN, OF PRINOEVILLE, ILLINOIS.

VALVULAR MECHANISIVI.

Specification of Letters Patent.

Patented Oct. 3, 1905.

Application iled October 17, 1904. Serial No. 228.714.

To all whom, it may concern.-

Be it known that I, HENRY S. AYLING, a citizen ot' the United States, and a resident of Bloomington, in the county of McLean and State of Illinois, have invented anew and Improved Valvular Mechanism, of which the following is a full, clear, and exact description.

The invention relates to a valvular mechanism particularly designed to control the steam movement in air-pumps employed in automatic air-brake systems.

T he prime object of the invention is to lprovide a mechanism which will economize the steam consumption in pumps.

A duplex air-pump is now commonly employed in connection with fluid-pressure brake systems in which the compressor-pistons come to a comparatively prolonged rest at the end ot' each stroke and in which the valve controlling the inlet ot' the motive steam is held open until the return movement of the piston has begun. This is highly disadvantageous, inasmuch as with the inlet-valve thus open the steam in the compressor-cylinder in time equalizes with the boiler-pressure, and there results from this condition a much higher pressure in the pump-cylinder and a greater consumption of steam than is necessary.

My invention involves a certain peculiar arrangement of the valves and their actuating parts which causes the steam-inlet valve to closeas the piston reaches the end of its stroke (thus preventing unnecessary consumption of steam) and the exhaust to be held covered during the time that the piston dwells at the end or' its stroke.

The invention involves various other features of major or minor importance, all of which will be fully developed hereinafter.

The accompanying drawings illustrate the preferred embodiment of my invention applied to control the steam movement in a duplex steam-driven air-pump-such, for example, as is made by the New York Air Brake Company for use in connection with their fluid-pressure railwaybrake apparatus. Said air-pump has two cylinders, one a low-pressure cylinder discharging into the other or high-pressure cylinder, in which the air is further compressed.

In the drawings like characters of reference indicate like parts throughout the views.

In said drawings, Figure l is a vertical section essentially on the line l 1 ot' Fig. 2, taken through the steam-cylinders and showing the two reversingvalves and the live and exhaust steam passages. Fig. 2 is a vertical cross-section taken through the low-pressure cylinder on essentially the line 2 2 of Fig. 1, showing the live and exhaust steam passages, the lowpressure reversing-valve, and the low-pressure distributing and cut-ofi' valves in crosssection. Fig. 3 is a horizontal section taken through the valvular mechanism on the plane of the live-steam passage, which is essentially that ot' the line?) 3 in Figs. 1 and 2. Fig. 4 is a horizontal section of the valvular mechanism, taken on the plane of the exhaust-steam passage, which is essentially that of the line 4 4 in Figs. 1 and 2. Fig. 5 is a detail view of one ot' the main or steam-distributing valves. Fig. 6 is a diagram illustrating the steam-cylinders, the pistons therein, with the live and exhaust steam passages, the reversing, distributing, and cut-oliP valves, and the various parts upon which the correct operation of my invention depends; and Fig. 7 is a detail View of one of the two-part bushings in which the main or steam-distributing valves, cut-off valves, and their differential actuating-pistons operate.

10 indicates the steam-cylinder connected with the high-pressure pump-cylinder, and 11 the steam-cylinder connected with the lowpressure pump-cylinder, which cylinders 10 and 11 for the purpose of illustration it may be assumed are identical with the steam-cylinders of the duplex air-pump forminga part of the New York Air Brake Oompanys automatic air-brake system, the high-pressure and low-pressure air-cylinders lying, respectively, above the steam-cylinders 10 and 11 and carrying compressor-pistons, respectively, in direct connection with the pistons ot' said cylinders. The lower head 12 ot' the steam-cylinders is bolted or otherwise suitably fastened to the cylinder-walls and carries the improved valvular mechanism in essentially the same position as in the commonly-known air-pump above referred to, and the piston-rods of both pistons are hollowed to receive the reversingrods 14, by means of which the reversingvalves 15 are automatically actuated at the end oi' each stroke oi' the steam-pistons, as will be fully understood from the prior art.

16 indicates the steam supply and 17 indicates the exhaust pipe. The steam-pipe 16 communicates with a horizontal steam-passage 18, formed in the walls of the steam- IOO head and preferably passing throug'h the l 29L and 30u open into said valve-cavity, re-

same from one end to the other, the end opposite the pipe 1G being fitted with a plug 19, securely yet removably to close the same. The exhaust-pipe 17 leads from an exhaustehamber 20, formed in the steam-head 12 at a point above the live-steam chamber 18, the passage 2O also in the preferred form of the invention passing' completely through the casing forming the steam-head 12 and being litted at the end opposite the pipe 17 with a plug' 21, similar in form and purpose to the plug 19. Formed in the steam-head at each side of the steam-chamber 18 and preferably in the horizontal plane thereof are the cavities 22 for the main valves and their immediately-allied parts. 1n each cavity 22 a twopart bushing is arranged comprising a cup part 23 and a sleeve part 2/1, the latter havingl a reduced diameter at the point 25 for the purpose which will hereinafter fully appear. The steam-passage 18 communicates with the cavities 22 by means of ports 26, extending from opposite sides of the steam passage or chamber, respectively, into the large diameters of the bushing-sections 2a, so that when steam is turned into the chamber 18 it is constantly supplied to the interior of said bushing-sections through said ports 26.

The steam-head 12, which forms, as will be apparent, the casing for the valvular mechanism, is provided with two pairs of ports 27 and 28 and 27and 28a, passing from the large diameter of each bushing-section 241 across the casing to the oppositely-situated bushing-section 23. r1`hese ports as they enter the large diameters of the bushing-sections 24 are relatively close to each other and as they enter the bushing-sections 23 are spread apart, as shown best in Fig. 3. The valve at the top of Fig. 3 immediately controls the steam-supply for the cylinder 11, and the valve at the bottom of Fig. 3 immediately controls the steam-supply for the cylinder 10. Leadingfrom the lower end of the low-pressure cylinder 11 into the cavity of the corresponding main or distributing valve (the top valve in Fig. 3) and communicating with said cavity in vertical line with the opening of the port 27n is a steam-port 29, which is intended to carry the steam to and from the lower side of the piston in the cylinder 11. Leading from the upper end oi' the cylinder 11 downward into the cavityv of the corresponding main or distributing valve (the top valve in Fig. 3) is a port 31"), which passes into the cavity of said valve at a point immediately above the opening' of the port 28 into said cavity. This port 30 is designed to lead the steam to and from the upper side of the piston in cylinder 10. Similar ports 29 and 30*l pass from the cavity of the main valve corresponding to the cylinder 10, (the bottom valve in Fig. 3,) respectively, to the lower and upper ends of the cylinder 10, as shown by the dotted lines in Fig. 2, and said ports l l l I spectively, above the ports 28 and 27 in the same. Passing from both valve-cavities intermediate the ports 29 and 30 and 29 and 30 thereof are ports 31, both of which lead to the exhaust-passage 20.

From the steam-passage 18 two passages 32 extend downward, and these are fitted with bushings 33, as shown. Operating in the said bushings are the before-mentioned reversingvalves 15, with which the reversing-rods 141 are connected, as before explained. rlhe said reversing-valves 15 are cornered eti' or grooved longitudinally to permit the steam to pass them. As shown best in Fig. 2, they are each provided with a port 34. These ports, when the valves arein the downward position shown in Figs. 1 and 2, are intended to place incommunication the exhausting-ports 35 and the feeding-ports 36 of each reversing-valve. The said feeding-ports, as shown best in Fig. 3, pass, respectively, to the ends of the mainvalve cavities 22 opposite the main valves to supply steam 'for operating said valve in one direction, as will be hereinafter fully explained, and the exhausting-ports 35 pass upward into the exhaust-cavity 20, as Fig. 2 illustrates. Vhen the valves 15 rise from the position shown in Figs. 1 and 2, they cover the exhausting-ports 35 and uncover the feeding-ports 36, and steam then passes down the sides of the reversing-valves and. into the feeding-ports from below the reversing-valves. rlhe main or distributing valves each comprises a c vlindric body portion 37, provided with a centrally-located indented port 38 and provided at its ends with a head 39 and L10, respectively, these heads being' spaced upon the ends of the body of the valve by means of pillars 41. (See Fig. 5.) The said distributing-valves are fast on stems 42 and are located within the bushing-sections 23. The stems 42 pass into the cylindrical bushingsections 24: and carry in the reduced part 25 a piston L13 and in the enlarged part of the said bushings 24 a piston 44. Intermediate said pistons 13 and et sliding' cut-otf valves L L5 are mounted fast on the stem.

wWhen the parts are in the position Shown in Fig. 3, in which, as will hereinafter fully appear, the piston of the cylinder 10 is dwelling at the end of its downstroke and the piston of cylinder 11 is on its upward stroke, the steam or distributing valve of the cylinder 11 (the top valve in Fig. occupies the following-described position with respect to the various ports communicating with the cavity 22 of said valve, to wit: The port 27, entering the cavity 22, is uncovered, opening into the space between the body 37 of the low-pressure valve and the head a() thereof. The in- The port IOO IIS

28, entering the bushing-section 23, is blanked by the body 37 of said valve. entering the bushing-section 24 0f said valve, is uncovered, and the port 27, entering the bushing-section 24 of.said valve, is blanked by the cut-ofi' valve 45. The distributingvalve of the cylinder (the bottom valve in Fig. 3) occupies the following position with respect to the various ports, to wit: The port 28, entering the bushing-section 24, is blanked by the cut-off valve 45. The port 27 entering the bushing-section 24, is uncovered. The port 28, entering the bushing-section 23, is blanked by the body 37 of said valve. The port 27, entering the bushing 23, is uncovered, this port 27 communicating by the space between the body 37 and head 4() with the port leading to the top of the cylinder 10, (see Fig. 6,) and the port 29, leading from the bottom of the cylinder 10, is in communication with the exhaust-port 31 by way of the indented port 38 of the body 37 of the valve.

Fig. 6 illustrates by diagram the position of allof the parts corresponding to that shown in Figs. 1, 2, and 3, and, referring to said diagram, it will be observed that the reversingvalve 15 of the piston in cylinder 11 is in position to place the ports and 36 of said reversing-valve in communication, exhausting steam from the right-hand side of the piston 44 of the valve of cylinder 10. When this takes place, the action of the steam on and between the differential pistons 43 and 44 will cause the pistons and the connected distributing-valve 37 of cylinder 10 to move rightward into the position shown in the drawings. The diagram in Fig. 6 also assumes that the piston of cylinder 10 is at the end of its downstroke, and consequently that the reversingvalve 15 of said high-'pressure piston is in its downward position, so as to place the ports 35 and 36 of the valve of cylinder 11,into communication and cause the valve to move leftward', as the diagram shows, owing to the action of the steam on the differential pistons 43 and 44 of said valve. This being the position of the parts, it will be observed that steam will pass from the cavity 18 through the port 26 into the cavity between the pistons 43 and 44,0f cylinder 10, and the port 27 being uncovered bythe cut-O' valve 45 steam will be permitted to pass this port across to the valve of cylinder 11 and through the space between said valve and its head upward into and through the port 29 to the Linder side of the piston or cylinder 11, moving said piston upward, as indicated by the arrow in the diagram. The said leftward movement of the valve 37 of cylinder 11 also results in throwing the exhaust-passage 31 and the port 30 into connection with each other, and steam will be exhausted from the top of the piston of cylinder l1 through the ports 30, 38, and 31 to the exhaust-cavity 20. This operation The port 28,`

will continue until the reversing-rod 14 on the piston of cylinder 11 moves upward the connected reversing-valve l5, such operation taking place when the piston of cylinder 11 reaches the end of its upward stroke. This will cause the exhaust-passage 35 of the valve of cylinder 10 to be closed and opening the steam-admitting passage 36 of said valve, so that steam passes down through the passage 32 past the said reversing-valve and through the passage 36 to the right-hand side of the piston 44 of the valve of cylinder 10, (the lower valve in Fig.6.) The steam will then act on both sides of the piston 44, and the pressure thereon will be equalized, whereupon the pressure on the piston 43 of said valve will act to shift the valve leftward, causing it to move the slide-valve so as to blank the port 27 and to uncover the port 28 and also causing the body of the valve to move so as to place the port' 29 in communication with the port 28 by reason of the space between the body 37 of the valve and the head 39 thereof. This said leftward movement of the valve of cylinder lO will further move the port 38 so as to connect the port 30 With the exhaustpassage 31 of the valve and to disconnect said port 30 from the port 27. vWhen these operations take place, the piston of cylinder 11 being at the end of its upward movement, the port 27 of the cylinder 11 will be covered and steam will be cut o' from the under side of the piston of said cylinder, the cut-oif valve 45 of the valve of cylinder l() nevertheless holding the steam-pressure in the cylinder 11 below the piston thereof as to keep said piston in its upper position until a reversal of its movement is desired.

As the valve 37 of cylinder 10 moves leftward, as above explained, and places the port 29 in communication with the port 28 steam passes from the valve-casing of cylinder 11 between the pistons 43 and 44 through the port 28, across the valve-cavity of cylinder 10, and into and through the port 29, starting the piston of cylinder 10 upon its upward movement. The above-referred-to leftward movement of the valve 37 also causes the port 38 to be moved so as to connect the port 30 with the exhaust-port 31, and this permits exhausting the steam from the upper side of y the piston, allowing said piston of cylinder 1() to move upward freely. This upward movement of the piston continues until the end of the stroke is reached, whereupon the reversing-valve connected to said piston 15 is raised, disconnecting the ports 35 and 36 ofthe valve of cylinder 11 and throwing the entering-port 36 into communication with the steam-passage 18 through the medium of the passage 32, before described. Steam will then enter through the passage 36 of the valve of cylinder 11 and act against the outer side of the corresponding piston 44, equalizing the pressure on its piston and permitting the pressure on the piston 43 to IIO shift le'ftward the valve and its connections,

said leftward movement of the valve and its connections resulting in connecting the port 29 with the exhaust-passage 3l of the valve of cylinder' l1, permitting the exhaust of the steam which was previously held in the cylinder ll Linder the piston thereof. Simultaneously the port 28u will be placed in com- .munication with the port 30 by reason of the space intervening between the valve-body 37 of cylinder 1l and the head 39 thereof,

causing steam to pass from the valve-cavity of cylinder ll between the pistons 43 and 44 thereof through the port 28", which is now uncovered by the cut-off valve 45 of cylinder l() across the valve-cavity of cylinder ll and into and through the port 30, exerting its pressure on top of the piston in cylinder 11 and causing the piston to begin its down-' ward movement. At the same time that the valve 37 of the cylinder l l shifted rightward,as above explained, it caused the cut-off valve 45 of cylinder ll to cover the port 28 and uncover theA port 27, and the valve 37 of cylinder 10 being at the end of its leftward movement opposite that shown in the diagram in Fig. 6 it will be observed that the steam-feed on the under side of the piston of cylinder lO through the port 29a will be cut ofiI from the cylinder 10, owing to the cut-olf valve 45 of cylinder 1l covering the port 28. This will hold the piston of cylinder ll in its upward position by the pressure of the steam already entered into the lower end of the cylinder; butit will prevent further supply of steam to the cylinder, and consequently it will prevent the unnecessary expenditure of this steam.

The piston of cylinder 11 was last referred to as moving downward, and when the end of its downward movement is reached it actuates the connected reversing-valve l5 again to assume the position indicated in the diagram, in which the ports 35 and 36 of the cylinder 11 are in communication, and steam is then exhausted from the right-hand extremity of the valve-cavity of cylinder l0, permitting the action of the steam on the adjacent faces of the differential pistons 43 and 44 to return the valve of cylinder l() and its cated in the diagram.

connections to the rightward position indilhis will cut off the steam-supply to the top of the piston in cylinder l1 through the port 30 by reason of the cut-off valve 45 of cylinder l() moving over A the port 28, covering' the same and prevent- 'ing the further entry of steam, the steam already entered into the top of the cylinder 1l acting nevertheless to hold the piston in its i lower position, as described. Vhen the slide- Ward movement, it causes the port 28 to be disconnected from the port 29 and said port 29 to be connected with the exhaust-port 3l of cylinder l0 through the port 38 of the valve 37 of said cylinder. This allows the steam to be exhausted from the under side of the piston of cylinder l0. Simultaneously the port 27 will be placed in communication with the port 30 through the space between the valve-body 37 of cylinder l() and the head 40 thereof, and steam will be admitted on top of the piston in cylinder 10, moving said piston downward, it being understood that the valve37 of cylinder 1l is yet in its rightward position. The downward movement of the piston of cylinder l() continues until said piston reachesits bottom position, whereupon the reversing-valve l5 of cylinder l0 is moved downward to connect the steam exhausting and feeding passages 35 and 36 and causing` the steam to be exhausted from the left-hand side of the piston 44 of the valve of cylinder l1. The steam then acting on the faces of the differential pistons 43 and 44 will serve to return the said valve to the leftward position, (shown in Fig. 6,) which results in the cut-off valve 45 of cylinder ll blanking the port 27, so as to cut off the steam-suppl y on the upper side of the piston of cylinder 1l, holding the steam on the upper side of the piston in order to retain it in this position. At the same time the valve 37 of cylinder l1 places the port 28" and the port 29 in communication with each other through the space between the body 37 of the valve and the head 40 thereof and causes live steam to be admitted on the under side of the piston of cylinder l1, again starting the upward movement thereof, as is indicated in the diagram, and also allowing the steam on top of the piston to be exhausted through the ports 30. 38, and 3l, as before explained. The result of this mechanism is therefore that I operate the steampistons, and consequently the air-compressing pistons connected thereto, as will be understood from the prior art, by an upward and downward movement followed by a prolonged dwell at the end of each movement, this action of the pistons being characteristic of the operation of the compound air-pump referred to above, and while holding the pistons at the end of their strokes I cut oif the steam from the source of supply, so as to prevent unnecessaryV expenditure of steam, retaining, nevertheless, a certain quantity of steam in the steam-cylinders whereby to hold the pistons in the Lipper or lower position, as the case may be. Ordinarily when the pistons reach the end of their stroke the full steam-head is continued against the pistons and the cylinders are allowed to equalize with the boilerpressure, this resulting in a great unnecessary expenditure of steam. I avoid this by cutting off the steam in the manner explained. In this novel function resides the essential part of my invention.

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Iof

Having thus described my invention, I claim as new and desire to secure by Letters Patentm l. In a valvular mechanism, the combination of a main or distributing valve, a cut-off valve coacting therewith, diierential pistons having connection with the valves, and means for controlling the fluid-pressure exerted on said pistons whereby to operate the valves.

2. In a valvular mechanism, the combination of a main or distributing valve, a cut-off valve coacting therewith, diii'erential pistons having connection with the valves, and means for controlling the Huid-pressure exerted on said pistons whereby to operate the valves, said means including periodically-operative reversing-valves.

3. In avalvular mechanism, the combination with a ported casing, of a main or distributing valve coacting therewith and comprisinga body with an indented port therein and heads respectively spaced from and connected with the ends of the body part of the valve, a sliding cut-o valve coacting with the main valve, and means for operating said valves.

4. In a valvular mechanism, the combination with a ported casing, of a main or distributing valve coacting therewith and comprising a body with an indented port therein and heads respectively spaced from and connected with the ends ot' the body part of the valve, a sliding cut-ofil valve coacting with the main valve, and means for operating the valves, said means comprising dierential pistons in connection with the valves and devices for controlling the application of fluidprcssure to said pistons.

5. In a valvular mechanism, the combination with a ported casing, of a main or distributing valve coacting therewith and cornprising a body with an indented port therein and heads respectively spaced from and connected with the ends ot' the body part of the valve, a sliding' cut-olf Ivalve coacting with the main valve, and means for operating the valves, said means comprisingditferential pistons in connection with the valves and devices including periodically-operative reversing-valves for controlling the application of fluid-pressure to said pistons.

6. In a duplex valvular mechanism, the combination with a ported casing of two distributing-valves, two cut-off valves respectively in connection with the distributingvalves, the cut-off valve of each distributingvalve controlling the ported communication to the opposite distributing-valve, and means for operating the valves.

7. In a duplex valvular mechanism, the

combination with a ported casing, of two distributing-valves, two cut-off valves arranged to operate respectively in Atime with the distributing-valves, the cut-olif valve of each distributing-valve controlling the ported communication to the opposite distributing-valve, and means for operating the valves.

8. In a duplex valvular mechanism, the combination with a ported casing, of two distributing-valves, two cut-ott valves arranged to operate respectively intime with the distributing-valves, the cut-off valveot` each distributing-valve controlling the ported communication to the opposite distributing-valve, and means for operating the valves through the medium of fluid-pressure.

9. In a duplex valvular mechanism, the combination witha ported casing, of two distributing-valves, two cut-olf valves arranged to operate respectively in time with the distributing-valves, the cut-off valve of each distributing-valve controlling the ported-communication to the opposite distributing-valve, and means for operating the valves through the medium of fluid-pressure and periodicallyoperative reversing-valves controlling said means.

10. In a Vduplex valvular mechanism, the combination with a ported casing, of two distributing-valves, two cut-oli:1 valves arranged to operate respectively in time with the distributing-valves, the cut-off valve of each distributing-valve controlling the ported rcommunication to the opposite'distributing-valve, and means for operating the valves,said means comprising differential pistons in connection with each set of valves and means for controlling the exertion ot' Huid-pressure on said pistons.

1l. In a duplex valvular mechanism, the combination with a ported casing, of two distributing-valves, two cut-oli` valves arranged to operate respectively in time with the distributing-valves, the cut-off valve of each distributing-valve controlling the ported communication to the opposite distributing-valve, and means for operating the valves,said means comprising dierential pistons in connection with each set of valves and periodically-operative reversing-valves controlling the application ot' fluid-pressure to said pistons.v

12. In a duplex valvular mechanism, the combination with a ported casing` of two main or distributing valves, a sliding cut-ott valve in connection with each main valve, the cutofl valves controlling the port communication to the opposite distributing-valves,and means for operating the valves.

13. In a duplex valvular mechanism, the combination with a ported casing, of two main or distributing valves, a stem in connection with each, a cut-off valve in connection with each stem, the cut-off valves controlling the port communication to the opposite distributing-valves,and means for operating the valves.

14. In a duplex valvular mechanism, the combination with a ported casing, of two main or distributing valves, a stem in connection lwith each, a cut-off valve in connection with IOO IIO

each stem, the cut-ofi1 valves controlling' the port communication to the opposite distributing'- valves, and means for operating the valves, such means comprising' diiierential pistons in connection with the valve-stems, and devices for controlling' the application of Huid-pressure to said pistons.

l5. In a duplex valvular mechanism, the combination with a ported casing, oi' two main or distributing valves, a stem in connection with each, a cut-ofiI valve in connection with each stem, the cut-ofi valves controlling the port communication to the opposite distributing' valves, and means for operating' the valves, such devices comprising differential pistons attached to said stems, and periodically operative reversingvalves con trolling' the application of' Huid-pressure to said pistons.

1. In a duplex valvular mechanism, the combination with two motor-cylinders and a ported casing, of a distribating-valve f'or each motor-cylinder, a cut-off valve for each motor-cylinder, means for operating' the valves, the cut-oliil valves being' respectively connectcd with the distributing-valves, and the cutottl valves controlling the port communication to the opposite distributing-valves.

17. In a duplex valvular mechanism, the combination with two motor-cylinders and a ported casing', ot' a distributing-valve for each motor-cylinder, a cut-off valve for cach motor-cylinder, and means for operating the valves by Huid-pressure.

18. In a duplex valvular mechanism, the combination with two motor-cylinders and a ported casing, of' a distributing-valve for each motor-cylinder, a cut-off valve for each motor-cylinder, and means for operating the valves, said means for operating the valves comprising differential pistons in connection therewith and devices for controlling the application of' fluid-pressure thereto.

19. In a duplex valvular mechanism, the combination with two motor-cylinders, and a ported casing', of a distributing-valve for each motor-cylinder, a cnt-olil valve for each motor-cylinder, and means 'for operating the valves, said means for operating the valves comprising' differential pistons in connectionl with the valves, and periodically-operative reversing-valves controlling the admission of fluid-pressure to said differential pistons, and in connection respectively with the pistons of said motor-cylinders.

20. In a duplex valvular mechanism, the combination with two motor-cylinders and a ported casing', of a distributing-valve foreach l the meansf'oroperatingthevalves,comprising i reversing-valves respectively in connection y with the pistons of the motor-cylinders.

2l. In a duplex valvular mechanism, the combination with two motor-cylinders and their pistons, and with a ported casing, of distributing-valves respectively for the motorcylinders, cut-ofi' valves respectively in connection with the distributing-valves, the cutoff valves controlling the port communication to the opposite distribnting-valves, means for operating; said valves by the application of fluid-pressure` and devices 'for controlling' said application of huid-pressure.

E22. In a duplex valvular mechanism, the combination with two motor-cylinders and their pistons, and with a ported casing, of' distributing-valves respectively for the motorcylinders, cut-ofi' valves respectively in connection with the distrihating-valves, the cuto` valves controlling` the port comm nnication to the opposite distributing-valves, means for operating' said valves by the application of tluid-pressnre, and devices for controlling' said application of finiti-pressure, said devices including; reversing' valves respectively connected with the motor-pistons.

23. In a duplex valvular mechanism, the combination with two motor-cylinders and their pistons, and with a ported casing', of' distributing-valves respectively for the motorcylinders, cut-oli'l valves respectively in connection with the distributiiig-valves, the cntofi'I valves controlling the port communication to the opposite distributing-valves, means for operating said valves by the application of' fluid-pressu re, and devices for eontrollingsaid application of Huid-pressure, said devices including reversing valves respectively connected with the motor-pistons, said reversing'- valves controlling the Huid-flow to the Valves ofl the cylinders opposite those with the pistons of which said reversing-valves have connection.

24E. In a duplex valvular mechanism the combination with two motor-cylinders and their pistons, and with a ported casing, of a distrilniting'walve 'for each motor-cylinder, a stem in connection with each valve, a cut-olf valve in connection with each stem, the cutofi' valve controlling' the port connection to the opposite distributing-valves, differential pistons connected with said stems, and reversingvalves respectively connected with the motor-pistons and controlling` the application of iluid-pressure to said ditferential pistons'.

25. In a duplex valvular mechanism, the colnbination with two motor-cylinders and their pistons, and with a ported casing, of a distrihating-valve for each motor-cylinder, a

stem in connection with each valve, a cut-ofi' valve in connection with each stem, the cutoff valve controlling' the port connection to the opposite distributing-valves, differential pistons connected with said stems, and reversing-valves respectively connected with the motor-pistons and controlling' the application of fluid-pressure to said differential pistons,

IOO

distributing-valve, a. eut-off Valve in connection with each stem, the cut-off valves controlling' the port communication to the opposite distributing-valves' and means for operating the valves.

In testimony whereof I have signed my name to this specification in the presence of two subseribing Witnesses.

- HENRY S. AYLING. Witnesses:

M. J. MCKINNEY, J. F. TIEDKE. 

